Answer:
Nevertheless.
Step-by-step explanation:
Coordinate ideas are those statements or ideas that are in coordination with each other. They are of equal importance in the sentence. And for the sentences to be in coordination with each other but also contrasting each other, the joiner "nevertheless" should be used. It means "however", "in spite of", and shows that even though the two sentences may be different in their opinions they need each other to show the full result. One is dependent on the other. "Nevertheless" may oppose/ contradict the sentence or point that has just been stated but that part of the sentence is also mandatory for the whole point to be valid.
eg. I don't like travelling. Nevertheless, I loved going to that ancient cave in the south of the border.